Differentiation Question 454
Question: If $ f(x)=x+2, $ then $ f’(f(x)) $ at x = 4 is
[DCE 2001]
Options:
A) 8
B) 1
C) 4
D) 5
Show Answer
Answer:
Correct Answer: B
Solution:
$ f(x)=x+2 $
Therefore $ {f}’(x)=1 $
\ $ {f}’(f(x))={f}’(x+2)=1 $ at $ x=4 $ .